The following report, co-written with Massachusetts PIRG, analyzes the 'outside spending' on federal Senate and House races in Massachusetts in the 2012 election cycle.

Outside spending refers to spending by groups independent of campaigns or political parties. These outside groups are legally prohibited from coordinating with campaigns. Citizens United v. FEC and subsequent cases that relied on its holdings led to increases in outside spending in elections by removing a number of restrictions and/or prohibitions on corporate and union political activity.